[igt-dev] [PATCH i-g-t] tests/perf: add a test for OA data polling reads using "small" buffers

[Dixit, Ashutosh]

On Fri, 27 Mar 2020 12:06:13 -0700, Lionel Landwerlin wrote:
>
> On 27/03/2020 21:03, Dixit, Ashutosh wrote:
> > On Fri, 27 Mar 2020 09:09:41 -0700, Lionel Landwerlin wrote:
> >> On 27/03/2020 06:50, Dixit, Ashutosh wrote:
> >>> On Thu, 26 Mar 2020 21:42:50 -0700, Ashutosh Dixit wrote:
> >>>> diff --git a/tests/perf.c b/tests/perf.c
> >>>> index 724f6f809..3dc757c3b 100644
> >>>> --- a/tests/perf.c
> >>>> +++ b/tests/perf.c
> >>>> +static void test_polling_small_buf(void)
> >>>> +{
> >>> /snip/
> >>>
> >>>> +
> >>>> +	igt_assert(abs(n_expect_read_bytes - n_bytes_read) < (0.10 * n_expect_read_bytes));
> >>>> +}
> >>>> +
> >>> I'd be wary of a 90% match on slow platforms like Atom? Maybe 80% is safer?
> >>
> >> Do we have any experiment showing them behaving differently?
> > No I don't have any data, but considering that in previous stable versions
> > we can only read < 10% of the data, I think it should be ok to go down to
> > 80%? So that we don't start getting unnecessary false alarms in CI, even
> > when the issue is fixed.
>
> Okay, for the record I get somewhere between 93~95% of expected reports on
> KBLGT2.

Yes I tried it and saw that. I already gave a R-b so we could probably
merge the patch after making that change (0.2 instead of 0.1 above), or do
you want me to post a new version with the change? Thanks!